[C ++] hex conversion

Binary Decimal turn

#include <cstdio>

int main() {
	int n;
	int a[1000];
	scanf("%d",&n);
	int i=n,j=0;
	while(i) {
		a[j]=i&1;
		i=i>>1;
		j++;
	}
	for(int i=j-1; i>=0; i--) printf("%d",a[i]);
	printf("\n");
	return 0;
}

Binary Coded Decimal

#include <cstdio>
#include <cmath>
#include <cstring>

int main() {
	char a[1000];
	scanf("%s",a);
	int sum=0,len=strlen(a);
	for(int i=0; a[i]; i++) if(a[i]=='1') 
		sum=sum+(1<<(len-i-1));
	printf("%d\n",sum);
	return 0;
}

Octal, decimal turn

#include <cstdio>

int main() {
    int a;
    scanf("%d",&a);
    printf("%o\n",a);
    return 0;
}

Decimal turn hex

#include <cstdio>

int main() {
    int a;
    scanf("%d",&a);
    printf("%x\n",a);
    return 0;
}

Octal, decimal turn

#include <cstdio>

int main() {
    int a;
	scanf("%o",&a);
    printf("%d\n",a);
    return 0;
}

Hex decimal turn

#include <cstdio>

int main() {
    int a;
	scanf("%x",&a);
    printf("%d\n",a);
    return 0;
}

Octal, hexadecimal turn

#include <cstdio>

int main() {
    int a;
	scanf("%o",&a);
    printf("%x\n",a);
    return 0;
}

Octal, hexadecimal turn

#include <cstdio>

int main() {
    int a;
	scanf("%x",&a);
    printf("%o\n",a);
    return 0;
}

Decimal turn x Hex (Universal)

#include <cstdio>

int main() {
    int y=0,k,n,x;
	char a[1000];
    char z='A';
    scanf("%d%d",&n,&x);
    while(n) {   
        y++;
        a[y]=n%x;
        n=n/x;
        if(a[y]>9) a[y]=z+(a[y]-10); 
        	else a[y]=a[y]+'0';
    }
    for(int i=y; i>0; i--) printf("%c",a[i]);
    printf("\n");
    return 0;
}

turn 10-m band (generic)

#include <cstdio>

int main() {
	char a[1000];
	int n,m,f=0;
	scanf("%s%d",a,&m);
	for(int i=0; a[i]; i++) {
		f*=m;
		if(a[i]>='A') f=f+(a[i]-'A'+10);
			else f=f+(a[i]-'0');
	}
	printf("%d\n",f);
	return 0;
}